Stephenson, 27, made 10 relief appearances for the Reds last season and 59 in 2019. In five seasons with the Reds, he was 10-13 with a 5.15 ERA across 104 appearances that included 22 starts.
Hoffman, also 27, went 2-1 with a 9.28 ERA in a career-high 16 relief appearances for Colorado in 2020. In five major league seasons with the Rockies, he was 10-16 with a 6.40 ERA in 68 games, including 38 starts. Colorado acquired him from the Blue Jays as part of the Troy Tulowitzki deal in 2015.
Hannah, 23, didn’t appear in a game in 2020. The Reds acquired him from Oakland in 2019.
Williams, 18, is a prospect from Castle Rock, Colorado, who was selected by the Rockies in the fourth round of the 2020 first-year player draft.